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Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

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Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#71

Post by rdl »

Mvandenbergh wrote: post #65
rdl wrote: post #25

Earlier quoted context omitted.

I am curious how you solve corrosion in a high pressure thermal cycling environment for what are presumably very tiny water fog nozzles. But maybe that is trade secret or whatever. Naively I'd just switch out the air for N2, since it's mechanically the same and cheap. But then, once you're using special gas, I'd look at using low and high molecular weight (say, He and maybe some long chain which isn't going to detona…

The problem with low molecular weight gasses is that they lead to embrittlement of any metal in contact with them and that they leak past your seals something fierce. Both due to their small size. He2 is also very expensive and H2 is very reactive which is not good either..

I want to build one of these: http://en.wikipedia.org/wiki/Ram_accelerator

Fortunately there's very little H2 involved (mainly I think in the later stages), it's mainly CH4.

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#72

Post by DaniFong »

jacquesm wrote: post #34

Congratulations Danielle, that's absolutely awesome. I'm still very sorry that you didn't get funding for some of your more off the beaten path ideas but this is as good as it gets. If there is one person that I wish would find a connection like this it is you, I'm sure you'll amaze us all with what you're going to achieve now that your toolbox is filled. This is really great news!

:)

Funding isn't the constraint now, it's time. But believe me there are more off the beaten path ideas where that came from ;-)

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#73

Post by DaniFong »

foobarqux wrote: post #31

Can you explain in detail what problem this solves and how it works to someone with a basic background in physics? Below is what my understanding: Current energy storage mechanisms (batteries) are inefficient. In theory one way to store energy that would be more efficient (why?) is to use the energy to compress air (with a conventional air compressor?). The air is stored in a container until it is converted to electr…

Hopefully our website might be more enlightening... lightsail.com

I give a 3 minute TR35 award talk on the concept at the emTech conference this year.

Starts at 5:27

http://www.livestream.com/emtech2012/video?clipId=pla_cdd4c6...

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#74

Post by jpdoctor »

DaniFong wrote: post #66
jpdoctor wrote: post #32

Earlier quoted context omitted.

> Once you exit the software bubble, almost everything, especially new technology, becomes a lot "harder" and takes a lot longer. I've done hardware in spades, so I'm well aware of the differences. In hardware, Series D was either a Mezzanine round or a something-has-gone-wrong = inside/major-dilution round Maybe the world has changed, but having no product at D is not a sign that things are going well on the biz sid…

You might be overfitting the data. The initial series A, and B were essentially a seed round. I can tell you, this was certainly an upround!

Congratulations. Was it led by outsiders?

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#76

Post by DaniFong »

BenoitEssiambre wrote: post #36
foobarqux wrote: post #31

Can you explain in detail what problem this solves and how it works to someone with a basic background in physics? Below is what my understanding: Current energy storage mechanisms (batteries) are inefficient. In theory one way to store energy that would be more efficient (why?) is to use the energy to compress air (with a conventional air compressor?). The air is stored in a container until it is converted to electr…

It is not super clear what the innovation is here as I am sure someone must have thought of storing compressors heat with water before. I think maybe the novel thing is to pass the water as a mist through the compressor cylinders where it can transfer energy from air much faster than if, for example there was just a heat transfer closed circuit around the cylinders. Their website states: "We have achieved these high…

The main thing is that the mist process is higher efficiency.

If you compress the air, let it heat up, and THEN cool it by mixing the air with water, the pressure will be high during the compression process, which will take a lot of energy to compress it, and then cool off and reduce in pressure. That's bad.

What you want is to keep the temperature as low as possible during compression, and to keep it as high as possible during expansion. We do this.

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#77

Post by DaniFong »

bluekeybox wrote: post #40
foobarqux wrote: post #31

Can you explain in detail what problem this solves and how it works to someone with a basic background in physics? Below is what my understanding: Current energy storage mechanisms (batteries) are inefficient. In theory one way to store energy that would be more efficient (why?) is to use the energy to compress air (with a conventional air compressor?). The air is stored in a container until it is converted to electr…

> Unfortunately compressed air is very hot and difficult to store. Not OP but a few comments on what you just said. If you ever tried to manually compress air in a metal pump (say when inflating a bicycle tire), you probably noticed that the outside of the pump gets very hot when you press down. That is because gases have a property of increasing their temperature when pressure increases. So now in order to maximize…

Water actually has the highest volumetric sensible (no phase change!) heat capacity of any substance on earth.

We don't rely on water vapor -- the problem is that at low temperatures there's very little vaporization that can even take place. This limits the heat transfer. Though there are alternative approaches that use this effect more fully.

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#78

Post by jacquesm »

DaniFong wrote: post #72
jacquesm wrote: post #34

Congratulations Danielle, that's absolutely awesome. I'm still very sorry that you didn't get funding for some of your more off the beaten path ideas but this is as good as it gets. If there is one person that I wish would find a connection like this it is you, I'm sure you'll amaze us all with what you're going to achieve now that your toolbox is filled. This is really great news!

:) Funding isn't the constraint now, it's time. But believe me there are more off the beaten path ideas where that came from ;-)

> But believe me there are more off the beaten path ideas where that came from ;-)

I wasn't in the least worried about that ;)

Take care!

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#79

Post by [deleted] »

guelo wrote: post #41
tryitnow wrote: post #26

What I find really intriguing about this is Thiel's participation - it's one thing to get funding from Khosla, who is a cleantech cheerleader, it's really amazing to get funding from Thiel, who is a cleanteach skeptic.

The Thiel quote made it sound like he invested in it because DoE rejected it. I'm not sure if having such an ideologue as an investor is a good idea, especially in the heavily regulated energy sector.

[deleted]

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#80

Post by DaniFong »

guelo wrote: post #41
tryitnow wrote: post #26

What I find really intriguing about this is Thiel's participation - it's one thing to get funding from Khosla, who is a cleantech cheerleader, it's really amazing to get funding from Thiel, who is a cleanteach skeptic.

The Thiel quote made it sound like he invested in it because DoE rejected it. I'm not sure if having such an ideologue as an investor is a good idea, especially in the heavily regulated energy sector.

To tell the truth I'm not sure we ever spoke with Thiel about the DOE/ARPA-E rejection. That was back in 2010. We've come a long way since then.
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